Maternal cardiometabolic and psychiatric factors driving breastfeeding success

Despite well-established benefits to mothers and children, breastfeeding rates fall short of WHO recommendations world-wide. To inform effective support strategies, we investigated how maternal factors influence breastfeeding success. We estimated the causal effects of sociodemographic, cardiometabolic, psychiatric, and perinatal factors on breastfeeding initiation, duration, and exclusivity, by triangulating Mendelian randomization and multivariable regression analyses using data from 72,653 mothers and 317,651 offspring across four European cohorts. Triangulated results robustly demonstrated that higher education, lower BMI, and lower propensities for smoking, insomnia, and depression improved breastfeeding success. Each additional 3.4years in education increased initiation odds by 2.32 folds (95% CI:1.94,2.77) and prolonged exclusive breastfeeding ({beta}=0.21standard deviations, 95% CI:0.17,0.24). Smoking, depression and BMI mediated 26%, 14%, and 12% of education effect on exclusivity, respectively. We found little evidence for effects of blood pressure, cholesterol and perinatal factors. We provide new robust evidence that maternal cardiometabolic and psychiatric factors partially mediate the causal effect of maternal education on breastfeeding. Interventions targeting maternal health could support breastfeeding, reducing maternal and infant health disparities.